Bloomington Convention

The Bloomington Convention was a meeting held in Bloomington, Illinois, on May 29, 1856, establishing the Illinois Republican Party. It was an attempt to unite Anti-Nebraska members of the Opposition Party into a single party. The convention adopted a party platform and nominated a ticket led by William Henry Bissell for Governor of Illinois. Bissell would be elected later that year, making him one of the first governors elected as a Republican.

By 1850, the Democratic Party had emerged as the leading political party in the United States. An uncertain stance on slavery led to the demise of the main Democratic competitor, the Whig Party. The slavery debate was briefly quelled by the Compromise of 1850, which settled several questions about the legality of slavery in new territories. However, the Kansas–Nebraska Act, proposed four years later, reignited tensions. The act would create two new territories and determined that slavery status there would be determined by a popular vote of residents.

Illinois had been a free state since its inception. The Kansas–Nebraska Act was designed by Senator Stephen A. Douglas and supported by his colleague James Shields, both Democrats. William Alexander Richardson led support of the bill in the United States House of Representatives, but failed to win the support of Democratic representatives Long John Wentworth and William Henry Bissell, as well as all Whigs. The act was passed on May 30, 1854, sparking a political upheaval. The Whig party dissolved and anti-slavery Democrats, including Bissell and Wentworth, abandoned their party; they united in a de facto Anti-Nebraska party, known as the Opposition Party.

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